Electronic equipment involving semiconductor devices are essential for many modern applications. Technological advances in materials and design have produced generations of semiconductor devices where each generation has smaller and more complex circuits than the previous generation. Capacitors (also known as condensers) are electrical components used to store potential energy in electrical fields and are designed for enhancing capacitance to a circuit of an electronic and electrical system, such as logic devices, CMOS image sensors (CIS), radio frequency integrated circuits (RFIC), and monolithic microwave integrated circuits (MMIC). Capacitive structures include, for example, metal-oxide-semiconductor (MOS) capacitors, p-n junction capacitors and metal-insulator-metal (MIM) capacitors. An MIM capacitor includes an insulator disposed between a lower and an upper electrode plates. The desired capacitance density is usually increased with increased integrated circuit density in dimension scaling. The capacitance density, however, may not be simply increased by increasing planar area of stacked MIM due to area conservation for contact vias.